\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Descriptive statistics, pre- and post-2008}
\begin{tabular}{l*{8}{c}}
\toprule
&\multicolumn{2}{c}{GSS}  &\multicolumn{2}{c}{HRS}  &\multicolumn{2}{c}{BHPS} &\multicolumn{2}{c}{SOEP} \\
&\specialcell{pre-\\ 2008}&\specialcell{post-\\ 2008}&\specialcell{pre-\\ 2008}&\specialcell{post-\\ 2008}&\specialcell{pre-\\ 2008}&\specialcell{post-\\ 2008}&\specialcell{pre-\\ 2008}&\specialcell{post-\\ 2008}\\
&            &            &            &            &            &            &            &            \\
\midrule
Age&        39.9&        42.6&        58.4&        63.3&        39.7&        41.6&        39.9&        43.1\\
&      (12.7)&      (13.7)&      (5.94)&      (5.87)&      (12.9)&        (13)&      (11.8)&      (12.3)\\
\addlinespace
Male&        .526&        .505&        .478&        .433&        .527&        .484&        .576&        .531\\
&      (.499)&        (.5)&        (.5)&      (.496)&      (.499)&        (.5)&      (.494)&      (.499)\\
\addlinespace
Married&        .615&        .539&        .718&        .741&        .577&        .534&        .587&        .524\\
&      (.487)&      (.499)&       (.45)&      (.438)&      (.494)&      (.499)&      (.492)&      (.499)\\
\addlinespace
Non-white&        .175&        .254&        .132&        .111&       .0381&       .0768&            &            \\
&       (.38)&      (.435)&      (.339)&      (.314)&      (.191)&      (.266)&            &            \\
\addlinespace
Immigrant&       .0948&        .129&       .0808&       .0746&       .0572&       .0995&        .123&        .139\\
&      (.293)&      (.335)&      (.272)&      (.263)&      (.232)&      (.299)&      (.328)&      (.346)\\
\addlinespace
Tertiary degree&        .263&        .328&        .543&        .676&        .472&        .452&         .27&        .325\\
&       (.44)&       (.47)&      (.498)&      (.468)&      (.499)&      (.498)&      (.444)&      (.468)\\
\addlinespace
Part-time worker&        .175&        .193&        .119&        .107&         .25&        .346&        .153&        .197\\
&       (.38)&      (.395)&      (.323)&      (.309)&      (.433)&      (.476)&       (.36)&      (.398)\\
\addlinespace
Union member&         .15&        .111&         .21&         .18&        .302&         .29&            &            \\
&      (.357)&      (.314)&      (.407)&      (.384)&      (.459)&      (.454)&            &            \\
\addlinespace
Temporary worker&            &            &            &            &       .0704&       .0657&        .113&        .131\\
&            &            &            &            &      (.256)&      (.248)&      (.316)&      (.338)\\
\addlinespace
Self-employed without employees$^a$&        .135&        .132&            &            &        .122&            &         .13&        .117\\
&      (.342)&      (.339)&            &            &      (.328)&            &      (.336)&      (.321)\\
\addlinespace
Self-employed with employees&            &            &            &            &       .0367&            &            &            \\
&            &            &            &            &      (.188)&            &            &            \\
\addlinespace
Job tenure&            &            &            &            &         5.2&        8.54&        9.92&          11\\
&            &            &            &            &      (6.84)&       (7.5)&      (9.95)&      (10.6)\\
\midrule
\(N\)&       14975&        5312&       28983&        6536&      113822&       77234&      172374&      159376\\
\bottomrule
\multicolumn{9}{l}{\footnotesize a: This row displays the mean for all self-employed workers for the US and Germany.}\\
\end{tabular}
\end{table}
